1. Field of the Invention
The present invention relates to magnetic head devices that include sliders having magnetic elements and supporters for supporting the sliders, and particularly, to a magnetic head device in which a slider is accurately maintained in position on a supporter.
2. Description of the Related Art
FIG. 12 is an exploded perspective view illustrating a part of a conventional magnetic head device.
A slider 30 is composed of a ceramic material, such as alumina-titan-carbide (Al2O3—TiC). A trailing-end surface 30b of the slider 30 is provided with a magnetic element 1 and an electrode unit P.
The magnetic element 1 is formed by thin-film deposition, such as a sputtering technique, and is a laminate including an MR head (reproducing head) and an inductive head for recording. The MR head has a magneto-resistive sensor, which may be a typical spin-valve type such as a GMR sensor and an AMR sensor.
A coil layer (not shown) of the inductive head included in the magnetic element 1 is connected to the electrode unit P via a lead layer (not shown). A sensing current is applied to the MR head from the electrode unit P.
A supporter 10 includes a flexure 11 that supports the slider 30, and a load beam 12 that supports the flexure 11. The load beam 12 is composed of, for example, a stainless leaf spring. The longitudinal sides of the load beam 12 are each provided with a bent segment 12a. The bent segments 12a have rigidity. An area extending from rear ends 12a1 of the bent segments 12a to a base segment 12c of the load beam 12 defines a leaf-spring functional portion 12d. The bent segments 12a do not extend into this leaf-spring functional portion 12d. The slider 30 is elastically supported above a recording medium due to an elastic force of the leaf-spring functional portion 12d. The base segment 12c of the load beam 12 defines a mounting portion, which is mounted to a driver (not shown) of a hard-disk device.
A front end portion of the flexure 11 is provided with a tongue segment 15, which is formed by partially cutting out the flexure 11. The slider 30 is fixed on the tongue segment 15 via an adhesive 14 composed of ultraviolet curing resin and thermosetting resin and also via conductive resin 13. The conductive resin 13 is for providing electrical conduction between the slider 30 and the flexure 11. The tongue segment 15 is provided with electrode connection parts 16 which are to be connected to the electrode unit P of the slider 30.
When a recording medium starts to rotate in response to an operation of a rotary driver, airflow is introduced into a space between the slider 30 and the top surface of the recording medium. Thus, the slider 30 moves above the recording medium while floating above the recording medium by a predetermined distance.
Japanese Unexamined Utility Model Registration Application Publication No. 5-79763 and Japanese Examined Utility Model Registration Application Publication No. 6-4456 each disclose a structure in which the slider is sandwiched by a front end portion of a suspension that holds the slider.
However, conventional magnetic head devices had problems in maintaining a stable floating distance between the slider and the recording medium.
According to a technique for mounting the slider 30 to the tongue segment 15 of the flexure 11 shown in FIG. 12, it is difficult to apply the resin uniformly. Moreover, the resin could possibly become deformed during the manufacturing process, such as the bonding process, and also during the use of the magnetic head device. With the increasing recording density in recording media in recent years, a magnetic head for recording/reproducing is demanded to be disposed closer to the recording medium as much as possible while still being set above the recording medium in a floating fashion. Specifically, the floating distance between a magnetic head and a recording medium has reached a range of about 9 nm to 10 nm. If the floating distance of a magnetic head is such a small value, a slight deformation in the resin that bonds the slider 30 to the tongue segment 15 of the flexure 11 may affect the floating distance. As a result, this could adversely affect the recording/reproducing properties of the magnetic head device.
Furthermore, with the higher sensitivity in magnetic reproducing heads in recent years, the magnetic reproducing heads now have weaker resistance to static electricity. Even though the conductive resin 13 is for providing electrical conduction between the slider 30 and the flexure 11, it has become difficult to protect such magnetic reproducing heads having weak resistance from static electricity by grounding via the conductive resin 13.
Furthermore, according to the magnetic head devices disclosed in Japanese Unexamined Utility Model Registration Application Publication No. 5-79763 and Japanese Examined Utility Model Registration Application Publication No. 6-4456, the slider is sandwiched in the horizontal direction. This means that the slider and the suspension (i.e. a flexure) can easily form a gap therebetween. This could easily lead to a fluctuation of the floating distance of the magnetic head. Particularly, although Japanese Examined Utility Model Registration Application Publication No. 6-4456 discusses a structure in which the slider is sandwiched using a shape-memory alloy, the mounting force of the slider in this structure may fluctuate in response to a change in the ambient temperature.